Physical Sciences and Mathematics Commons^™

Decision Theory Based Models In Insurance And Beyond, Raymond Ye Zhang

Electronic Thesis and Dissertation Repository

Everyday, we make difficult choices under uncertainties. The decision making process becomes even more complicated when more agents get involved: one must consider their interactions and conflicts of interest because the final outcome is based not only on an agent's decision but on everybody's.

In insurance industry, companies try to avoid making large claim payments to policyholders (commonly known as insureds) by purchasing reinsurance policies from reinsurance companies (the reinsurer). Each policy details conditions upon which the reinsurer pays a share of the claim to the insurance company (also known as the cedent or the insurer). To reach an agreement, …

Tip-Enhances Raman Spectroscopy, Enabling Spectroscopy At The Nanoscale, Nastaran Kazemi Zanjani

Electronic Thesis and Dissertation Repository

The knowledge on the chemical and the structural properties of substances benefits strongly from characterization methods that can provide access to the sample’s nanoscale building blocks. Not only should the sensitivity of these methods approach a high detection limit up to single molecule, but also the accessible spatial resolution must enable chemical imaging of individual nanoscale features of the substances. High resolution imaging is often provided by electron microscopes through methods such as transmission electron microscopy (TEM) and scanning electron microscopy (STM), nevertheless, these methods lack offering chemical information. Surface-enhanced spectroscopy was developed to improve the sensitivity of the chemical …

Exploring The Synthesis And Coordination Chemistry Of Zwitterionic Main Group Compounds, Jonathan W. Dube

Electronic Thesis and Dissertation Repository

Traditionally low coordinate and low oxidation state main group compounds are isolated utilizing hard anionic donors based on carbon and nitrogen based ligands. Conversely, employing anionic phosphines for this role has been essentially unexplored. In this context, this dissertation describes the synthesis of a number of main group complexes, ranging from group 13 to group 15, utilizing the bis(phosphino)borate ligand class in a supporting role. The remote anionic borate backbone renders the complexes zwitterionic and provides access to unique compounds that possess structures, and exhibit onwards reactivity, that is very different to the analogous compounds stabilized with neutral phosphines. For …

On The Parallelization Of Integer Polynomial Multiplication, Farnam Mansouri

Electronic Thesis and Dissertation Repository

With the advent of hardware accelerator technologies, multi-core processors and GPUs, much effort for taking advantage of those architectures by designing parallel algorithms has been made. To achieve this goal, one needs to consider both algebraic complexity and parallelism, plus making efficient use of memory traffic, cache, and reducing overheads in the implementations.

Polynomial multiplication is at the core of many algorithms in symbolic computation such as real root isolation which will be our main application for now.

In this thesis, we first investigate the multiplication of dense univariate polynomials with integer coefficients targeting multi-core processors. Some of the proposed …

Protein Conformational Studies By Hydrogen/Deuterium Exchange Mass Spectrometry, Antony D. Rodriguez

Electronic Thesis and Dissertation Repository

Proteins are biological macromolecules responsible for the majority of all physiological processes. In order to properly function proteins are required to adopt highly ordered structures. These structural aspects may be found within a single protein or arise from multi-protein complexes. Here hydrogen/deuterium exchange mass spectrometry (HDX-MS) is employed as a tool to determine the extent of protein higher order structure. Exposure to D₂O-based solvent causes the heavier isotope to exchange with amide hydrogens in the polypeptide backbone. This exchange is mainly dependent on protein conformation because the presence of stable hydrogen-bonded secondary structure will impede the incorporation of …

The Electrochemistry Of Hydrogen Peroxide On Uranium Dioxide And The Modelling Of Used Nuclear Fuel Corrosion Under Permanent Disposal Conditions, Linda Wu

Electronic Thesis and Dissertation Repository

This thesis reports a series of investigations examining the corrosion process of used nuclear fuel under permanent disposal conditions. The motivation of the project is that the safety assessment of deep geological disposal of spent nuclear fuel requires a fundamental understanding of the processes controlling fuel corrosion which could lead to the release of radionuclides to the geosphere from a failed container.

One primary objective of this project was to develop a computational model in order to simulate fuel corrosion under the disposal conditions. A series of simulations based on COMSOL were designed and developed to determine the influence of …

Deep Learning Via Stacked Sparse Autoencoders For Automated Voxel-Wise Brain Parcellation Based On Functional Connectivity, Céline Gravelines

Electronic Thesis and Dissertation Repository

Functional brain parcellation – the delineation of brain regions based on functional connectivity – is an active research area lacking an ideal subject-specific solution independent of anatomical composition, manual feature engineering, or heavily labelled examples. Deep learning is a cutting-edge area of machine learning on the forefront of current artificial intelligence developments. Specifically, autoencoders are artificial neural networks which can be stacked to form hierarchical sparse deep models from which high-level features are compressed, organized, and extracted, without labelled training data, allowing for unsupervised learning. This thesis presents a novel application of stacked sparse autoencoders to the problem of parcellating …

Adaptive Edge-Guided Block-Matching And 3d Filtering (Bm3d) Image Denoising Algorithm, Mohammad Mahedi Hasan

Electronic Thesis and Dissertation Repository

Image denoising is a well studied field, yet reducing noise from images is still a valid challenge. Recently proposed Block-matching and 3D filtering (BM3D) is the current state of the art algorithm for denoising images corrupted by Additive White Gaussian noise (AWGN). Though BM3D outperforms all existing methods for AWGN denoising, still its performance decreases as the noise level increases in images, since it is harder to find proper match for reference blocks in the presence of highly corrupted pixel values. It also blurs sharp edges and textures. To overcome these problems we proposed an edge guided BM3D with selective …

A Computational Linguistic Approach Towards Understanding Wikipedia's Article For Deletion (Afd) Discussions, Wanting Mao

Electronic Thesis and Dissertation Repository

With the thriving of online deliberation, Wikipedia's Article for Deletion (AfD) discussion has drawn a number of researchers' attention in the past decade. In this thesis we aim to solve two main problems: 1) how to help new users effectively participate in the discussion; and 2) how to make it efficient for administrators to make decision based on the discussion. To solve the first problem, we obtain a knowledge repository for new users by recognizing imperatives. We propose a method to detect imperatives based on syntactic analysis of the texts. And the result shows a good precision and reasonable recall. …

Optimizing The Analysis Of Electroencephalographic Data By Dynamic Graphs, Mehrsasadat Golestaneh

Electronic Thesis and Dissertation Repository

The brain’s underlying functional connectivity has been recently studied using tools offered by graph theory and network theory. Although the primary research focus in this area has so far been mostly on static graphs, the complex and dynamic nature of the brain’s underlying mechanism has initiated the usage of dynamic graphs, providing groundwork for time sensi- tive and finer investigations. Studying the topological reconfiguration of these dynamic graphs is done by exploiting a pool of graph metrics, which describe the network’s characteristics at different scales. However, considering the vast amount of data generated by neuroimaging tools, heavy computation load and …

Investigating Genotype-Phenotype Relationship Extraction From Biomedical Text, Maryam Khordad

Electronic Thesis and Dissertation Repository

During the last decade biomedicine has developed at a tremendous pace. Every day a lot of biomedical papers are published and a large amount of new information is produced. To help enable automated and human interaction in the multitude of applications of this biomedical data, the need for Natural Language Processing systems to process the vast amount of new information is increasing. Our main purpose in this research project is to extract the relationships between genotypes and phenotypes mentioned in the biomedical publications. Such a system provides important and up-to-date data for database construction and updating, and even text summarization. …

Quantum Optics Of Polaritonic Nanocomposites, Chris Racknor

Electronic Thesis and Dissertation Repository

In this thesis, we study the quantum optical interaction in polaritonic nanocomposites. These systems are made by the combination of two or more micro- or nano-scale structures with complementary optical properties, such as polaritonic materials, excitonic materials, photonic crystals (PCs), quantum dots (QDs), waveguides, couplers, metal nanorods (MNRs), bionanoparticles. The nanocomposites systems studied included QDs doped within a polaritonic PC, an excitonic waveguide coupler, and a metamaterial waveguide. Also addressed are systems consisting of MNRs paired with biological labelling dye or QDs.

The application of a strain field, known as the acousto-optic effect, was found to control photon transmission in …

Peptidomimetic Ghs-R1a Agonists As Pet Imaging Agents For Prostate Cancer, Milan M. Fowkes

Electronic Thesis and Dissertation Repository

Contemporary diagnostic techniques for prostate cancer (PCa) have a limited ability to distinguish between benign and malignant disease. The ghrelin receptor has a differential expression in normal, benign and cancerous prostatic tissue. Targeting this receptor with 18F-radiolabelled peptidomimetics would enable differentiation between these disease states via PET imaging. A series of 19F-peptidomimetics were synthesized and characterized by HRMS, HPLC and 1 H-NMR spectroscopy in order to test locations for 18F radioisotope insertion. Competitive receptor binding assays using HEK293/GHS-R1a cells were used to evaluate compound binding affinities. This led to the identification of two lead compounds: [1-Nal4,Lys5(4-FB)]G-7039 (IC50 = 69 nM) …

Shear Zone Influence On The Emplacement Of A Giant Pegmatite: The Whabouchi Lithium Pegmatite, Quebec,Canada, Laurisha Bynoe

Electronic Thesis and Dissertation Repository

The Whabouchi pegmatite is within a transpressional high-strain zone of a metamorphosed volcano-sedimentary belt. A well-developed subvertical transposition foliation and a subvertical stretching lineation are present in this zone. The main body of the Whabouchi pegmatite is parallel to the transposition foliation and branching veinlets from this body have been folded and boudinaged by shear zone deformation. Thus suggesting that the Whabouchi pegmatite intruded syn-kinematically during the deformation of the shear zone. Previously, the Whabouchi pegmatite gave a zircon age of 2577 + 14Ma. The Whabouchi pegmatite is linked geochemically and geochronologically to a large pegmatite body to the south …

The Aricheng Basement-Hosted Albitite-Type Uranium Deposit, Roraima Basin, Co-Operative Republic Of Guyana, South America., Jim A. Renaud

Electronic Thesis and Dissertation Repository

The Kurupung batholith is situated in a west dipping mylonite zone within theTransamazonian-aged Mazaruni granite greenstone terrane. Mylonitic shearing is a result of regional sinistral strike-slip faulting during the post-collisional stage of the Transamazonian orogenic cycle. Deformation was active between 2103 +/- 3 Ma, the age of the batholith, and 1995 +/- 15 Ma, the age of hydrothermal uranium and zircon mineralization. Mineral chemical and geochemical characterization of the batholith identifies a uranium-enriched low-Ti sanukitoid generated by partial melting of slab metasomatized mantle which retained unresorbed Cr-bearing mantle inclusions. Rapid unroofing to greenschist facies conditions at approximately 2094 +/- 5 …

Study Of Virus Dynamics By Mathematical Models, Xiulan Lai

Electronic Thesis and Dissertation Repository

This thesis studies virus dynamics within host by mathematical models, and topics discussed include viral release strategies, viral spreading mechanism, and interaction of virus with the immune system.

Firstly, we propose a delay differential equation model with distributed delay to investigate the evolutionary competition between budding and lytic viral release strategies. We find that when antibody is not established, the dynamics of competition depends on the respective basic reproduction numbers of the two viruses. If the basic reproductive ratio of budding virus is greater than that of lytic virus and one, budding virus can survive. When antibody is established for …

Statistical Methods For The Analysis Of Rna Sequencing Data, Man-Kee Maggie Chu

Electronic Thesis and Dissertation Repository

The next generation sequencing technology, RNA-sequencing (RNA-seq), has an increasing popularity over traditional microarrays in transcriptome analyses. Statistical methods used for gene expression analyses with these two technologies are different because the array-based technology measures intensities using continuous distributions, whereas RNA-seq provides absolute quantification of gene expression using counts of reads. There is a need for reliable statistical methods to exploit the information from the rapidly evolving sequencing technologies and limited work has been done on expression analysis of time-course RNA-seq data. In this dissertation, we propose a model-based clustering method for identifying gene expression patterns in time-course RNA-seq data. …

Resting State Functional Magnetic Resonance And Diffusion Tensor Imaging Of Hemiplegic Cerebral Palsy Patients Treated With Constraint-Induced Movement Therapy: Predictors And Clinically Correlated Evidence Of Neuroplasticity, Kathryn Y. Manning

Electronic Thesis and Dissertation Repository

Hemiplegic cerebral palsy is characterized by unilateral upper limb impairment and patients often compensate by performing most tasks with their unaffected arm. Constraint-induced movement therapy (CIMT) directly combats this learned non-use by casting the unaffected arm and forcing the patient to repetitively practice skills with the hemiplegic limb. Subjects with hemiplegic cerebral palsy were recruited from Holland Bloorview Kids Rehabilitation Hospital, Thames Valley Children’s Centre and McMaster Children’s Hospital. MRI acquisitions and clinical evaluations were collected at baseline, 1 and 6-months later. The case group participated in a CIMT camp after baseline evaluations and was compared to an untreated control …

Computing And Approximation Methods For The Distribution Of Multivariate Aggregate Claims, Tao Jin

Electronic Thesis and Dissertation Repository

Insurance companies typically face multiple sources (types) of claims. Therefore, modeling dependencies among different types of risks is extremely important for evaluating the aggregate claims of an insurer. In the first part of this thesis, we consider three classes of bivariate counting distributions and the corresponding compound distributions introduced in a 1996 paper by Hesselager. We implement the recursive methods for computing the joint probability functions derived by Hesselager and then compare the results with those obtained from fast Fourier transform (FFT) methods. In applying the FFT methods, we extend the concept of exponential tilting for univariate FFT proposed by …

Hydrology And Biogeochemistry Of A Bog-Fen-Tributary Complex In The Hudson Bay Lowlands, Ontario, Canada, Thomas A. Ulanowski

Electronic Thesis and Dissertation Repository

The Hudson Bay Lowlands (HBL) contains 26 Gt C sequestered in a 2 meter thick layer of peat which blankets a quarter of Ontario, Canada. The hydrological and chemical influence of the HBL peatlands to surface waters is recognized, but information on peatland runoff processes and the evolution of groundwater through this vast, carbon-rich landscape remain scant. This study focused on elucidating the groundwater flow patterns of a bog-fen-tributary complex in the central region of the HBL, and estimating exports of groundwater, dissolved organic carbon (DOC), total (THg), and methyl (MeHg) mercury during the 2011 ice-free season. Hydrometric data, combined …

Isotopic Fingerprinting Of Shallow And Deep Groundwaters In Southwestern Ontario And Its Applications To Abandoned Well Remediation, Mitchell E. Skuce

Electronic Thesis and Dissertation Repository

Abandoned hydrocarbon wells in southwestern Ontario can act as conduits for Sulphur water, brines, and hydrocarbons from deep Paleozoic bedrock aquifers. Such leakage may pose a threat to shallow groundwater and the environment. Cost-effective plugging of these wells requires knowledge of the sources of the leaking fluids. This study characterizes the isotopic compositions (δ18OH2O, δ2HH2O, δ34SSO4, δ18OSO4, δ13CDIC, 87Sr/86Sr) of groundwaters in the region, which are distinct in different bedrock formations. A Bayesian mixing model was applied to these data to develop a tool for identifying the source(s) of leaking fluids. The geochemical data also improve our understanding of groundwater …

High Multiplicity Strip Packing, Devin Price

Electronic Thesis and Dissertation Repository

An instance of the two-dimensional strip packing problem is specified by n rectangular items, each having a width, 0 < w_n ≤ 1, and height, 0 < h_n ≤ 1. The objective is to place these items into a strip of width 1, without rotations, such that they are nonoverlapping and the total height of the resulting packing is minimized. In this thesis, we consider the version of the two-dimensional strip packing problem where there is a constant number K of distinct rectangle sizes and present an OPT + K - 1 polynomial-time approximation algorithm for it. This beats a previous algorithm …

Classification Of W-Groups Of Pythagorean Formally Real Fields, Fatemeh Bagherzadeh Golmakani

Electronic Thesis and Dissertation Repository

In this work we consider the Galois point of view in determining the structure of
a space of orderings of fields via considering small Galois quotients of absolute Galois
groups G _F of Pythagorean formally real fields. Galois theoretic, group theoretic and
combinatorial arguments are used to reduce the structure of W-groups.

Statistical Analysis And Computer Modelling Of Volcanic Eruptions, Laura Anabelle Sanchez

Electronic Thesis and Dissertation Repository

Volcanism is an important mechanism by which internal heat is transported to the Earth's surface and volcanic eruptions are the results of the dynamics of a complex system and are characterized by non-trivial temporal correlations. Understanding the processes involved in volcano formation and magma ascent are crucial to develop better hazard assessment techniques. This study focuses on three main points: understanding caldera formation in the solar system, investigating the global temporal behaviour of volcanic eruptions and understanding the nonlinear interactions taking place in the solid crust which lead to an eruption.

In chapter 2, I first examine the distribution of …

I. Accurate 50-200 Kev Proton Stopping Cross Sections In Solids Ii. Lateral Growth Of Si Wires On Si (100) Substrate, Sergey Dedyulin

Electronic Thesis and Dissertation Repository

Medium energy ion scattering (MEIS) is used to determine the elemental depth profile in the first few hundred angstroms of a sample. The interpretation of MEIS spectra requires an accurate knowledge of the rate at which the ions lose their energy - the stopping cross section, ε. The rate of energy loss has been fairly well investigated, both experimentally and theoretically, in elemental and compound targets at high energies (E>400 keV/amu). However, in the medium ion energy range where stopping cross section typically has a maximum, experimental data are scarce while most of the existing theories fail to give …

Micro-Computed Tomography Semi-Empirical Beam Hardening Correction: Method And Application To Meteorites, David R. Edey

Electronic Thesis and Dissertation Repository

X-ray micro-computed tomography (μCT) is able to non-destructively provide high- resolution 3D images of the internal structures of dense materials such as meteorites. The widespread availability of instruments capable of biomedical micro-computed tomography means there is ample access to scanners for the investigation of geomaterials, but the scan data can be susceptible to artifacts such as beam hardening, a consequence of high X-ray attenuation in these dense materials.

A semi-empirical correction method for beam hardening and scatter that can be straightforwardly applied to available biomedical scanners is proposed and evaluated. This method uses aluminum as a single calibration material to …

Surface Functionalization And Bioconjugation Of Nanoparticles For Biomedical Applications, Longyan Chen

Electronic Thesis and Dissertation Repository

Colloidal inorganic nanoparticles (NPs) have been attracting considerable interest in biomedicine, from drug and gene delivery to imaging, sensing and diagnostics. It is essential to modify the surface of nanoparticles to have enhanced biocompatibility and functionality for the in vitro and in vivo applications, especially in delivering locally and recognizing biomolecules. Herein, the goal of this research work is to develop advanced NPs with well-tailored surface functionalities and/or bio-functionality for the applications in cell tracking and analytes detection.

In the first project, quantum dots incorporating with gelatin nanoparticles (QDs-GNPs) have been developed for bioimaging applications. Two different approaches have been …

Extracting Vessel Structure From 3d Image Data, Yuchen Zhong

Electronic Thesis and Dissertation Repository

This thesis is focused on extracting the structure of vessels from 3D cardiac images. In many biomedical applications it is important to segment the vessels preserving their anatomically-correct topological structure. That is, the final result should form a tree. There are many technical challenges when solving this image analysis problem: noise, outliers, partial volume. In particular, standard segmentation methods are known to have problems with extracting thin structures and with enforcing topological constraints. All these issues explain why vessel segmentation remains an unsolved problem despite years of research.

Our new efforts combine recent advances in optimization-based methods for image analysis …

A Molecular Simulation Study On Micelle Fragmentation And Wetting In Nano-Confined Channels, Mona Habibi

Electronic Thesis and Dissertation Repository

We performed coarse-grained molecular-dynamics (MD) simulations to study the structural and dynamical properties of surfactant micelles in equilibrium and under Poiseuille-like flow in a nano-confined geometry. We used the MARTINI force-field to model the interactions between water molecules, counter-ions, and sodium dodecyl sulfate (SDS) surfactants. SDS surfactant was chosen as the standard model because of its potential application in drug delivery systems. First, we focused on the self-assembly of SDS in equilibrium. To form stable spherical mi- celles, we ran simulations in the isothermal-isobaric ensemble (NPT) on a system of free SDS surfactants, counter-ions and water molecules. We studied the …

Automatic Multi-Model Fitting For Blood Vessel Extraction, Xuefeng Chang

Electronic Thesis and Dissertation Repository

Blood vessel extraction and visualization in 2D images or 3D volumes is an essential clinical task. A blood vessel system is an example of a tubular tree like structure, and fully automated reconstruction of tubular tree like structures remains an open computer vision problem. Most vessel extraction methods are based on the vesselness measure. A vesselness measure, usually based on the eigenvalues of the Hessian matrix, assigns a high value to a voxel that is likely to be a part of a blood vessel. After the vesselness measure is computed, most methods extract vessels based on the shortest paths connecting …